Analog Devices Inc./Maxim Integrated MAX16155ABAB+T

Overview

MAX16155ABAB+T from Analog Devices is a nanoPower supervisory circuit with integrated watchdog timer, designed for ultra-low-power microcontroller-based systems. It monitors VCC supply voltage (1.2V–5.5V), asserts open-drain RST on undervoltage (factory-trimmed 1.5V threshold), and detects software faults via WDI input with 1s nominal watchdog timeout. Its 6-pin SOT23 package supports portable medical devices and battery-powered meters requiring long-term reliability at -40°C to +125°C.

For engineers reviewing the MAX16155ABAB+T datasheet, MAX16155ABAB+T pinout, MAX16155ABAB+T application, or MAX16155ABAB+T equivalent, key selection criteria include its 400nA typical supply current, WD_EN enable/disable control, ±2.5% reset threshold accuracy, and compatibility with fast-rising VCC transients (>50µs) in space-constrained industrial and healthcare designs.

Technical Context

The MAX16155ABAB+T implements dual independent timing circuits: a reset timeout block triggered by VCC crossing the factory-set 1.5V threshold with 128ms minimum delay, and a watchdog timer activated only when WD_EN is high, featuring 100ms startup delay and 1s nominal timeout. Both outputs-RST and WDO-are open-drain with guaranteed VOL ≤ 0.3V at ISINK = 50μA.

Its internal architecture includes a precision voltage reference trimmed to ±2.5% over temperature, hysteresis of 0.4% for noise immunity, and glitch rejection of 300ns on WD_EN. The device disables watchdog monitoring entirely when WD_EN is low, eliminating false timeouts during system initialization or sleep modes.

Key Specifications

Pinout & Package

MAX16155ABAB+T uses a 6-pin SOT23 package (package code U6+1, outline 21-0058), with 1.27mm × 2.2mm footprint and JEDEC-standard thermal resistance (θJA = 115°C/W on four-layer board).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar supervisory and watchdog applications.

Compared with MAX16153ABAB+T and TPS3808G15DBVR, the MAX16155ABAB+T uniquely combines ultra-low 400nA current, hardware WD_EN control, and 1.5V precision reset in a standard SOT23 footprint-enabling longer battery life and safer firmware suspend/resume in portable medical and industrial edge nodes.

Availability

MAX16155ABAB+T is available at Aetrix Electronics and suitable for portable medical diagnostics, smart utility metering, and industrial sensor nodes requiring stable component supply across extended temperature ranges and multi-year production cycles.

Supply support for MAX16155ABAB+T includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Analog Devices is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, automotive, communications, and healthcare markets.

The MAX16155ABAB+T belongs to Analog Devices' nanoPower supervisor family, engineered specifically for battery-constrained applications where sub-μA current, precision voltage monitoring, and configurable watchdog behavior are essential for functional safety and longevity.

FAQ

What is the factory-set reset threshold voltage for MAX16155ABAB+T?

The MAX16155ABAB+T has a factory-trimmed reset threshold of 1.5V, specified with ±2.5% accuracy across the full -40°C to +125°C operating temperature range and 1.2V–5.5V supply voltage. This value is fixed per the "B" suffix in the part number and cannot be adjusted externally. The threshold hysteresis is 0.4%, ensuring robust immunity to supply noise during brownout recovery.

How does the WD_EN pin affect watchdog operation in MAX16155ABAB+T?

In MAX16155ABAB+T, the WD_EN pin is an active-high logic input that enables or disables the internal watchdog timer. When WD_EN is driven low, the watchdog circuit is fully disabled and ignores all WDI transitions; when pulled high, the watchdog activates after a maximum 300μs setup time and begins monitoring WDI edges. This allows precise runtime control-such as disabling during bootloader execution or deep-sleep modes-without firmware modification.

What is the reset timeout period for MAX16155ABAB+T, and how is it determined?

The MAX16155ABAB+T features a minimum reset timeout period of 128ms, as indicated by the "C" suffix in the ordering code (MAX16155ABAB+T → "C" = 128ms). This delay begins after VCC rises above the 1.5V threshold plus hysteresis and ensures the microcontroller receives a clean, sustained reset signal before starting code execution. The timeout is factory-programmed and not user-adjustable.

Can MAX16155ABAB+T operate from a 1.2V supply, and what are the implications?

Yes, MAX16155ABAB+T operates from 1.2V to 5.5V, making it compatible with near-dead battery conditions in coin-cell applications. At 1.2V, the device maintains full functionality-including 1.5V threshold monitoring, 400nA supply current, and open-drain RST/WDO outputs-but VOL is guaranteed ≤0.3V only at ISINK = 50μA. For heavier loads, VCC ≥ 1.8V is recommended to ensure reliable output drive.

What package type and footprint does MAX16155ABAB+T use, and is it RoHS-compliant?

MAX16155ABAB+T uses a 6-pin SOT23 package (outline 21-0058, package code U6+1) with 1.27mm × 2.2mm body size and standard JEDEC lead pitch. The "+T" suffix confirms tape-and-reel packaging and RoHS compliance (lead-free finish). Land pattern number 90-0175 applies, and thermal resistance is θJA = 115°C/W on a four-layer PCB-critical for thermal design in sealed medical enclosures.